Say g’bye to summer hummers once global climate warms
By PAUL KOBERSTEIN
For a good part of the year, the colorful rufous hummingbird can be spotted all over Portland. After nesting and breeding here in the summer and fall, these feisty hummers migrate some 2,000 miles southward to winter in Mexico.
But over the next few decades, the tiny bird is expected to become increasingly rare in Portland. Climate change is likely to alter its travel plans, which include the longest annual migration of any hummingbird species. Its range is likely to shift northward, according to predictions in a new report from the National Audubon Society. The rufous, like hundreds of other birds, is likely to relocate to new habitat featuring its preferred temperatures, precipitation and food.
If indeed it is forced to leave, the rufous will be missed for the shimmering iridescent colors and flashy performances it brings to Portland parks and backyards. The male is distinguished by its cinnamon and red throat, and the female by its green crown and back feathers. Known as the feistiest of 17 hummingbird species in North America, it is also one of the smallest. It rarely exceeds 4 inches in height.
“This is a bird that everyone loves, as it zips around people’s backyards,” says Bob Sallinger, conservation director of the Audubon Society of Portland. “It is a bird that people see courting and doing territorial displays at their hummingbird feeders.”
Within a few generations, Portland could become at best just a stopover for the species, rather than a seasonal nesting spot. “It’s possible we won’t have rufous hummingbirds staying here in Portland for any amount of time,” Sallinger says.
Dozens of local species at risk
The rufous hummingbird won’t be the only bird species affected by climate change, according to the Audubon study. The first-of-its-kind analysis concludes that 314 bird species nationwide will lose more than half of their current range by 2080. That includes 92 bird species common in Oregon. Each may become endangered by then, which means at that point they could be plunging toward extinction.
Another 97 bird species face climate threats that could lead them to attain endangered status.
Climate change also is expected to transform the face of bird-friendly places like Portland’s Forest Park. The northern pygmy owl and varied thrush, which breed there, and the red crossbill, a regular visitor, face the loss of up to 98 percent of their habitat over the next 70 years, the report says.
At best, future generations of Oregonians may see these species only as winter visitors.
In addition, the migrating flock of the popular Vaux’s swift, which makes its home in a chimney at Chapman School in Northwest Portland for several days every September, could be similarly affected.
Climate change could upend the local range of raptors such as the bald eagle, ferruginous hawk and osprey, as well as several kinds of game birds and waterfowl. Outside of Portland, climate change could lead to the disappearance of the sage grouse in Eastern Oregon; the brown pelican, a frequent denizen of the Oregon Coast; and the northern spotted owl, which depends heavily on ancient forests.
What individuals can do
Over the last seven years, Audubon scientists have used hundreds of thousands of observations and sophisticated climate models to predict how more than 550 bird species in North America will react to climate change. This work defined the climate conditions birds need to survive, then mapped where those conditions will be found in the future as the Earth’s climate responds to increased greenhouse gases.
The basic message delivered by the new study is not particularly new. Over the past two decades, hundreds of peer-reviewed studies have documented ways birds are responding to and being impacted by a changing climate — not only by shifting their ranges but by encouraging them to lay eggs earlier in the year.
A rapid decline in bird populations would not be unprecedented. The passenger pigeon crashed from 2 billion birds to none in just 40 years.
The climate study did not consider the impacts from other environmental changes, such as habitat loss, that have been documented by annual bird surveys going back more than a century. Portland Audubon has put 230 birds on its “watch list” of species that need immediate conservation help for reasons unrelated to climate change. In areas where a strong conservation investment has been made, such as protecting wetlands or the restoration of natural habitat in backyards, bird populations are growing. But when habitat destruction collides with climate change, birds face a bleak future, Sallinger says.
“If folks are looking for things to do, I would suggest the Audubon/Columbia Land Trust backyard habitat certification program,” he says. That program currently serves residents within Multnomah County and Lake Oswego.
“As with reducing our own individual carbon footprint, small things can add up to big things,” Sallinger says. “Naturescaping our yards and neighborhoods can assist with carbon sequestration and also provide habitat for wild birds passing through our landscape.”
On a larger scale, he urges people to get involved by “advocating for the protection and restoration of the most important landscapes for birds in Oregon at places like Malheur and Klamath.”